This invention relates in general to grommets that are used in holes formed through panels in vehicles to facilitate the passages of wires or other articles therethrough. In particular, this invention relates to an improved structure for a grommet that is more effective and less expensive than known grommets.
Most vehicles are provided with one or more panels or similar barriers that separate one portion of the vehicle from another. For example, a firewall is commonly provided in a vehicle to separate an engine compartment thereof from a passenger cabin. In many instances (both when the vehicle is manufactured and when installing an aftermarket device), it may be necessary or desirable for one or more wires or other articles to pass through these panels. To accommodate this, it is known to provide one or more holes through the panel to allow the wire or other article to pass therethrough.
However, the existence of such a hole can at least partially defeat the main purpose of the panel, which is to separate one portion of the vehicle from another. For example, a hole formed through a firewall can undesirably provide a pathway for water and other contaminants to pass from the engine compartment of the vehicle into the passenger cabin. Also, the presence of such a hole can undesirably provide a conduit through which noise can pass from the engine compartment of the vehicle into the passenger cabin. Lastly, the formation of such a hole can create a relatively sharp edge, which could cause damage to the wire or other article extending therethrough.
To address these problems, it is known to provide a grommet in the hole formed through the panel. Typically, the grommet includes a hollow cylindrical body that is formed from a plastic or elastomeric material. One or more flanges may be provided on the hollow cylindrical body to engage opposed sides of the panel to retain the grommet within the hole. The wire or other article extends through the hollow cylindrical body of the grommet The grommet minimizes the amount of open space extending through the panel, thereby minimizing the size of the pathways for contaminants and noise to pass from the engine compartment of the vehicle into the passenger cabin. Also, the grommet protectively covers any relatively sharp edges that might be present on one or both of the opposed sides of the panel, thereby protecting the wire or other article extending therethrough.
As mentioned above, the need for a hole through a firewall of a vehicle may arise not only when the vehicle is manufactured, but also later when installing an aftermarket device on the vehicle. To facilitate the installation of an aftermarket device on the vehicle, it is known to provide a grommet with two or more passageways, a first passageway that is used when the vehicle is initially manufactured and a second passageway that may be used when an aftermarket device is subsequently installed on the vehicle. The provision of these two or more hollow passageways eliminates the need to form a second, separate hole through the panel.
Although known grommets having multiple passageways have functioned satisfactorily, it would be desirable to provide an improved structure for a grommet that is more effective and less expensive than known grommets.